Dynamic color imaging method and system

ABSTRACT

The present invention provides color images of tissue characteristics for determining the existence can location of tissue anomalies. An image of tissue is received, divided into pre-determined portions and accompanied by X and Y coordinates describeing the tissue relative to a subject. Characteristic data of the tissue is received for each portion of the image and is displayed by color according to characteristic data value. Characteristic data can also be determined and displayed for each portion of the image over multiple levels. Multiple images, one for each level, can be scrolled through for a common set of X and Y coordinates of tissue. Or, a three dimensional image is created, having respective levels displayed simultaneously, with color representative of the tissue characteristics for the entire depth of the tissue investigated. Additionally, color images are developed that compare and display differences in characteristic data of tissue over time.

RELATED APPLICATIONS

This application claims priority from pending U.S. ProvisionalApplication Ser. No. 60/238,350, filed Oct. 6, 2000, entitled “A DynamicColor Density Mapping System”. This application is also acontinuation-in-part of U.S. application Ser. No. 09/890,501, filed Aug.1, 2001, which is the National Stage of International Application No.PCT/US00/02341, filed Jan. 29, 2000, which claims priority to U.S.application Ser. No. 09/241,193, filed Feb. 1, 1999, which is acontinuation-in-part of U.S. application Ser. No. 08/957,648, filed Oct.24, 1997, now U.S. Pat. No. 6,192,143.

FIELD OF THE INVENTION

This invention relates to a method and system for creating images oftissue characteristics, and more particularly to a method and system forcreating dynamic color images of tissue density, the color imagesdisplaying variations of tissue density over selected regions tofacilitate the accurate and early detection of tissue anomalies.

BACKGROUND OF THE INVENTION

The early detection of anomalous human tissue, and in particular thedetection of undesirable tissue such as fat, fibrous tumors, orcancerous tissue is a much felt need. For example, recent findingsindicate that one out of eight women will develop breast cancer, thesecond leading cause of death in women. The earliest indication ofbreast cancer generally is the occurrence of a painless lump, sometimesassociated with nipple discharge and skin retraction. Unfortunately,later, more obvious and less survivable indications of cancer aregenerally due to metastases to bone, brain, lungs and liver.Accordingly, early detection of anomalus tissue and tissue changes isessential for improvement of survivability and effective treatment.Attempts at early detection through monthly self-examinations andmammography have proven beneficial but have not satisfied the need formore effective methods of early detection and corresponding treatment.

By way of example, if small lumps, less than 20 mm, can be detectedearly they can then be diagnosed by a biopsy and treated should the lumpbe found to be malignant. Accordingly, early detection allows for lessinvasive treatment, such as a lumpectomy with possible radiationtreatment of axillary nodes making less likely the need for a modifiedradical mastectomy with axillary node dissection. In addition, throughearly treatment the five-year survival rate can be improved by as muchas 85 percent. Absent early detection, distant metastasis can reducesurvival rates to 10 percent or less. The present invention addressesthis very critical need.

Although early detection is essential, it can be difficult to achieveeven by skilled physicians. Monthly self-examinations are helpful,particularly when followed by the examination of a physician in theevent a mass is self-detected. It is, however, difficult for anunskilled individual to do a thorough examination, and unlikely thatvery small lumps will be detected.

Presently, anomalies in tissue, particularly breast tissue, are detectedmostly by periodic palpation by the hand of a physician or radiographicmammography. To be effective, however, hand palpation must be frequent,particularly in older women, to detect tumors before the tumorsmetastasize. Unfortunately, the subjective nature of hand palpation andthe frequency required to make these examinations effective createlimitations rendering hand palpation examinations ineffective due toinconvenience, availability, and cost In addition, mammography istroublesome due to the concern of accumulated radiation exposure fromfrequent mammograms. Furthermore, mammography, unlike palpation, can belimited because very small tumors are not detected, particularly in thedenser breast tissue of younger women.

In addition to anomalies, it is also important that changes in tissuestructure, and changes in tissue characteristics, be detected andmonitored over time. The problem, therefore, is how to detect minorchanges in tissue. For example, hand palpation of tissue may not revealsmall characteristic changes or anomalies within breast tissue until thechanges are so substantial, or the anomalies so prominent, that they areno longer responsive to early treatment.

Another problem limiting the effectiveness of hand palpation is theinability to record, retain, and at a later time recall, historical dataof prior detected anomalies, including location and the nature of thechanges over time. This is particularly the case for soft anomaloustissue located further from the surface of the skin, having diametersless than 10 mm. Also, anomalies deeper in the tissue of large breastsare particularly difficult to detect by hand palpation. Even ifdetected, it is often not possible to characterize the tissue or changesin the tissue due to the subjective nature and lack of standards forhand palpation, which almost entirely depends on the skill andsensitivity of the examining physician.

Accordingly, the present invention addresses each of the aforementionedproblems and urgent needs. The present invention provides methods andsystems for early detection of tissue anomalies and changes in tissuecharacteristics through color imaging of tissue characteristics, thecolor images displaying variations of predetermined tissuecharacteristics over selected regions of tissue to facilitate theaccurate and early detection of tissue anomalies, even very smallanomalies. The present invention also addresses the need to objectivelydetermine tissue characteristics and produce, maintain, and compareimages of these characteristics, over time, the images mapping selectedregions of tissue to track characteristic changes over time.

SUMMARY OF THE INVENTION

The present invention is a method and system for developing color imagesof tissue characteristics, the color images displaying variations ofpre-determined tissue characteristics over selected regions of tissue tofacilitate the accurate and early detection of tissue anomalies.

In one aspect of the invention, a method and system develops imagesdisplaying characteristics of tissue by first developing an image of thetissue. The image is divided into pre-determined portions and isaccompanied by data describing a first and a second coordinate of thetissue relative to a subject body for each portion of the image. Thesystem receives characteristic data of the tissue for each portion ofthe image, then associating a color to the characteristic data for eachportion of the image. The color associated to the characteristic data isbased upon the value of the characteristic data, so that the colordisplayed, for each portion of the image, portrays the degree ofvariation of the value of the characteristic data relative to that forother portions of the tissue investigated. The system then displays thecolor for each portion of the image.

In one aspect of the invention, the data describing the first and thesecond coordinate of the tissue relative to the subject body is receivedfrom a camera. The characteristic data can be received from a palpationdevice (i.e., a detection head having one or more palpation probes). Alocation head may provide positional data associating the characteristicdata detected by the palpation device with that portion of the imagedisplaying that coordinate of the tissue detected.

In another aspect of the invention, the system further calculates andrecords a size of tissue for any predetermined characteristic value. Thecharacteristic data may relate to one property, or may relate to acombination of properties. Examples properties are tissue density,temperature, color, resistance, conductivity, impedance, ultrasound andsampling information. Further properties may include a distance traveledby a palpation probe, a velocity of travel of the palpation probe and atime of palpation at each probe contact point with tissue.

In another aspect of the invention, when the characteristic dataincorporates multiple properties, the system carries out an intermediatestep of associating code to the multiple properties of characteristicdata before color is assigned. First, a set of codes is assigned to eachproperty incorporated into the characteristic data. A specific codewithin the set is assigned for each property based upon the valuedetected for that property for each portion of the image. A resultantcode is calculated for each portion of the image based on a formula thatconsiders each of the included properties and the specific code assignedfor that property. Then, a color is associated to the resultant code.

In another aspect of the invention, characteristic data of tissue isreceived for each portion of the image for each of a plurality of thirdcoordinate values related to that portion of the image. The systemprocesses and displays multiple image layers, each image layercorresponding to similar first and second coordinates of the tissuerelative to the subject body. Each image layer can be scrolled throughto provide incremental views of depth for any given coordinate.

In another aspect of the invention, the multiple image layers aredisplayed simultaneously, one over another, to create a virtual,three-dimensional image. The color displayed for each portion of thethree-dimensional image is selected based on a formula that considersthe characteristic data of the tissue for each layer simultaneouslydisplayed for that portion.

In another aspect of the invention, the system processes recordedinformation related to characteristic data determined for selectedfirst, second and third coordinates of tissue and programmably comparesthe data with previously determined data related to the same coordinatesof the same tissue. The system displays an image of the respectivetissue, and color is assigned to each portion of the image based uponany change, and degree thereof, in the characteristic data for thatportion of the image. The change displayed could be directed to adifference, in absolute value, of the characteristic data compared foreach portion of the image, or the change displayed could be a firstderivative analysis of the characteristic data compared, or the changedisplayed could be a combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, there is shown in thedrawings a form which is presently preferred; it being understood,however, that this invention is not limited to the precise arrangementsand instrumentalities shown.

FIG. 1 is an illustration of a detection device for detecting anomaliesin human tissue according to the present invention;

FIG. 2 is an illustration of a patient positioning platform for use withthe detection device shown in FIG. 1;

FIG. 3 is an illustration of a detection head and actuator according tothe present invention;

FIGS. 4 and 4 a illustrate a position and movement measurement deviceused with the detection head and actuator shown in FIG. 3;

FIG. 5 is an illustration of a locator head assembly according to thepresent invention;

FIG. 6 is an illustration of a vertical positioning mechanism for usewith a detection device;

FIGS. 7 through 10 illustrate alternate embodiments of a detection headaccording to the present invention;

FIG. 11 illustrates a palpation tip for a detection head according tothe present invention;

FIG. 12 illustrates a detection head having a plurality of parallelpalpation tips according to the present invention;

FIGS. 13 a and 13 b illustrate an actuator with an encoder according tothe present invention;

FIG. 14 illustrates an optical locating head and detection head mountedto a carriage according to the present invention;

FIG. 15 illustrates the internal components of an alternate embodimentof a locator head assembly according to the present invention;

FIG. 16 illustrates a detection head and actuator having a samplingdevice according to the present invention;

FIG. 17 illustrates an optical locating head and detection head having asampling device mounted to a carriage according to the presentinvention; and

FIGS. 18 a through 18 c illustrate alternate embodiments of samplingdevices according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, wherein like numerals indicate likeelements, there is shown in FIG. 1 an illustration of one embodiment ofan apparatus 10 for detecting anomalies in human tissue. In one aspectof the invention, the apparatus 10 includes a carriage (also referred toas a robot arm) 11 that is mounted at a proximal end to a horizontalsupport 12 for movement therealong, and a detector 14 (also referred toas a detection head) that is mounted at the distal end of the carriage11. The detector is shown in more detail in FIGS. 3 and 4 and is used todetect the characteristics of tissue by palpation. A locator 16, forlocating the position of a patient relative to some reference, ismounted to the carriage 11 for movement therewith. Data is produced bythe palpation device and collected, stored and displayed in a mannerthat will capture details of the detected anomalies for comparison withhistorical data The invention provides data about the tissue underinvestigation by means of an automated biopsy and treatment by means ofsurgical attachments for the delivery of radiologic, chemotherapeutic,or laproscopic surgery.

For example, the digital information can be received, stored, processedor displayed in a similar manner to existing medical devices such as aCAT scan or MRI. The present invention also produces multi-dimensionalimages viewed on conventional computer monitors. Images are producedusing color to indicate areas of differing tissue density. These imagesare further enhanced by combining tissue density information with tissuecolor and temperature information to detect and track small tumors indiscrete tissue areas.

Horizontal Movement

In one embodiment of the invention, the support structure of which isdetailed in FIG. 6, the detector 14 is positioned over the patient andprovided with horizontal movement by a horizontal support 12 that ismounted on a vertical support mechanism 18, allowing the horizontalsupport 12 to move in a vertical direction. The horizontal support 12includes a traveler 20 that rides on bearings 22 along rods or tubes 24that are secured at their ends to end blocks 26, 28. A lead screw 30 isdriven by a drive motor 34 and extends between a pair of end blocks 26,28 and bearings 32. Lead screw 30 extends through correspondinglythreaded openings 36 of the traveler 20 so that the traveler 20 willmove to the right or left as the lead screw 30 is rotated in onedirection or the other, and limit switches 37 are used to prevent overtravel of the traveler 20. Guide rods 38 extend vertically through theend blocks 26, 28 so that the horizontal support 12 can be movedvertically by means of a lead screw 40 that extends vertically throughone end block 28.

The carriage 11 includes a base 42 secured to the traveler 20. A motor44 within the base 42 rotates a screw 46 that is threaded into anintermediate body 48 to raise and lower the intermediate body 48 as thescrew 46 is rotated one way or the other. A pair of guide rods 50 extendthrough a bracket 52 to guide movement of the intermediate body 48. Alower body 54 is secured to the intermediate body 48 for rotationrelative thereto. A motor 56 is mounted on the intermediate body 48 withthe lower body 54 mounted on the motor shaft 58 for rotation with theshaft 58.

Vertical Movement

The detector 14 is positioned over the patient and provided withvertical movement by a mechanism for raising and lowering the entirecarriage 11, as shown in FIG. 6. The carriage 11 is supported by a pairof vertical guide rods 38 that extend from a sturdy base 156 to a topplate 158. A pair of end blocks 26, 28 support the horizontal support 12and provide vertical movement therealong.

A motor 160 rotates a sturdy lead screw 40 threaded through a block 28.An upper limit switch 164 and a lower limit switch 166 prevent movementof the horizontal support 12 beyond desired limits. For a very strong,sturdy assembly, the base 156 will rest on the floor or a sub-floor sothat the platform 67 could be positioned within the frame formed by thebase 156, the top plate 158 and the guide rods 38.

Positioning Arm

An arm 61 is pivotally mounted at a pivot 62 on a bracket 64 that ismounted on the distal end of the lower body 54. A motor 60 on the lowerbody 54 drives a pulley 63 on the arm 61 through a jackshaft 65. Thus,the entire carriage 11 can be moved horizontally by the horizontalsupport 12, and vertically by the vertical support 18. The lower body 54of the carriage 11 can be rotated 360°. The arm 61 carries the detector14 which can be pivoted through at least 120°. The arm 61 can also carryand operate other devices such as, but not limited to, attachments forthe delivery of acoustic, radiologic, chemotherapeutic treatments orlaparoscopic surgery. The combination of movements just described permitthe detector 14 to be positioned in any desired location relative to anyportion the surface of human body, particularly a breast.

Although a particular positioning arrangement of the detector 14 hasbeen described, it is understood that the invention can include any typeof positioning system that will provide several degrees of freedom ofmovement for the detector 14 or other devices.

Position and Location System

In one embodiment of the invention, an investigation of a selected bodypart or region is started by positioning the patient on a platform (alsoreferred to as a bed) 67 that is affixed to a position adjustingassembly 69, such as that shown in FIG. 2. The platform 67 is typicallypositioned below the detector 14 of FIG. 1. The platform 67 has acomfortably padded upper surface and a matrix board 66 with a locationpattern 71, that is typically positioned adjacent to the shoulders ofthe patient 68.

The matrix board 66 and pattern 71 are used to maintain registrationbetween the specific points of the patient's body under investigationand the acquired measured data. In addition, the matrix board 66 andpattern 71 are used to maintain registration between subsequentmeasurements taken at different times for the same patient 68.

For example, optical measuring means such as, but not limited to, avideo camera, a fiducial reference target, or a laser location devicecan be used to locate the exact position of the patient or selected bodyparts such as arms, shoulders and neck relative to the matrix board 66and its pattern 71 during an investigation.

In subsequent investigations, the patient 68 is positioned on theplatform 67, the optical system, with or without the aid of adaptivesoftware techniques, will correlate prior and presently collectedlocation data and measurement data. Further, movement by the patient 68that may introduce errors in the measured data can be corrected duringthe investigation by error correction techniques provided by the opticalsystem. Although it is desirable that the patient 68 be placed in thesame position for each investigation, it is not required since that theinvention can correct for any change in position by means of positionreference data collected during each periodic investigation.

Referring to FIG. 2, the underside of platform 67 includes conventionaltubular bearings through which a pair of horizontal guide rods 70 pass.A central threaded rod 72, driven by a motor 76, engages end bearings74. As the motor 76 rotates, the platform 67 is moved right to left. Theplatform 67 is similarly moved up and down by means of a pair of guiderods 78 secured to end walls 80 of assembly 69 and driven by a motor 84that rotates a threaded rod 82 which moves the platform 67 as desired.

The invention provides a means to control the position of the patientfor consistent reinvestigation. This is accomplished by means of theplatform 67 and a locator (also referred to as a location device,sensor, or head) 16, shown in FIG. 5. The locator 16 provides accuratelocation information for positioning the patient 68 on the platform 67or for correlating the data with subsequent or prior measurements bymeans of geometric translation which can be achieved by patternrecognition or reference to a fixed fiducial reference.

For example, a digital camera 134 is used to produce a digitized imageof the tissue under investigation. The image is then compared by acomputer system or technician to prior or subsequent images. A whitelight source 136 can be used to produce a three-dimensional image. Asshown in FIG. 5, the light source 136 is employed with an auto-focussystem having a lens 138, and a lead screw 140 rotatable by a motor 142and threaded through a lens mount bracket 144 for focusing a light spoton the surface of the tissue under investigation. The spot of light ismoved transversely and focused at different depths along the tissuesurface. Data of the focus position of the 6lens 138 is collected andused to produce a three-dimensional image of the tissue surface.

In another aspect of the invention, as shown in FIG. 5, a laser scanner146 may be used to create a three-dimensional image. The laser scanner146 includes a laser emitter 148 and a focusing system 150 for producinga focused laser spot on the surface of the tissue under investigation.For example, a laser operable in the range of 680-820 nm with a powerlevel about 0.0095 should provide sufficient laser power to produce animage without damaging the tissue under investigation.

In all aspects of the invention, prior and subsequently collected imagedata can be used to translate position data of the tissue underinvestigation. This feature provides enhanced capabilities in theexamination of anomalies in the tissue under investigation. For example,a three-dimensional image can be divided into a matrix of cubes orslices with geometric indicia (e.g., a cube might be identified as cube2, 4, 9 on an x-y-z axis basis) and locations can be directly comparedbetween the light spot image and the probe palpation locations.

Palpation Systems

One embodiment of the detector 14, according to the present invention,is shown in FIG. 3. The detector 14 is shown with a removable connection86 for attachment onto a rotatable arm 61. The detector 14 has apalpation probe housing 90 for supporting a palpation probe or finger 92and a sensor 94. The sensor 94 includes, but is not limited to, a devicefor sensing distance, acoustic waves, x-rays, MRI, color, andtemperature. The sensor 94 may also be mounted to the detector's mainhousing 87. The palpation probe 92 is designed to simulate a physician'sfinger during a palpation investigation like that in a manual breastexamination. In a preferred embodiment, the palpation probe 92 iscomposed of a disposable material, such as, but not limited to, glass orplastic.

Distance is measured by means of a sensor 94, which is an autofocussystem like that used in cameras. The auto-focus system can provideprecise data such as the distance between the breast surface and a knownreference point within the sensor. In another aspect of the invention, aplurality of spaced range finders can be used to measure the angle withrespect to the breast surface so that the orientation of the palpationprobe 92 is maintained at a pre-determined angle such as, but notlimited to a, perpendicular to the tissue under investigation.

Color is sensed by a color sensing device such as a photo-detectiondiode or spectrum detection sensor. In addition, a prism or diffractiongrating for dispersing incoming light and refracting each color of lightto an independent photoelectric sensor may also be used.

Referring to FIG. 3, in one aspect of the invention the palpation probe92 is secured to the distal end of a first shaft 100 which is slidablyconnected to the housing 90 and pivoted, at its proximal end, to thedistal end of a first arm 102 at a pivot point 104. The first arm 102 isrotatable about an axis 106 that is centrally located along a second arm98. The proximal end of the first arm 102 is pivotally connected to adrive shaft 100 at a second pivot point 110. When the drive shaft 108 ismoved axially by an actuator located within an actuator housing 112,which is shown in detail in FIG. 4, the first shaft 100 and thepalpation probe 92 move a proportional distance in the oppositedirection.

The motion of the palpation probe 92 is then measured to determine time,distance traveled, velocity, and resistance encountered by the probe 92as it comes in contact with the tissue under investigation. For example,an optical reading device 126 having a laser source is located in areader housing 114 for detecting movement of the palpation probe 92 bymeans of an optical encoded gradient 113 attached to the drive shaft108. The parameters of time, distance traveled, and rate thereof, areused to determine a characteristic value of the tissue underinvestigation in response to the feedback resistance experienced by thepalpation probe 92 when it is pressed against the tissue underinvestigation.

To further improve the accuracy of the measurements, a position errorcorrection sensor 116 is used in cooperation with a position detectionmember 119 such as, but not limited to, an optical gradient, inertialdisplacement device or motion sensor, that is attached to the firstshaft 100 to detect and correct positioning errors. The position errorcorrection sensor 116 is used to correct movement and position errors ofthe components of the detector 14. Movement of the palpation probe isaccomplished by the activation of magnetic coils 118, which are detailedin FIG. 4. Slight changes in position of the tissue under investigation,like that caused by breathing, can be sensed by the palpation probe anda corresponding position correction signal can be sent to selected coilsof the magnetic coils 118 to correct displacement errors.

In one embodiment of the invention, the palpation probe 92 is moved by aseries of electromagnetic coils 118 that are arranged in a uniformlyspaced relationship along a central tube 120. In a preferredconfiguration, the electromagnetic coils 118 may be formed as acontinuous helix to form a solenoid. An end shaft 122 is axially securedto the proximal end of the drive shaft 108 and extends into a tube 120.

An end shaft 122 is formed from a magnetic material so that when thecoils 118 are actuated sequentially, beginning with the coil adjacent tothe end shaft 122, the magnetic forces in the coils 118 will pull theend shaft 122 into the tube 120. Alternately, the coils 118 are actuatedindividually in a sequence or by applying incrementally increasingvoltages to the coils 118. The extension of the drive shaft 108 iscontrolled by the movement of the end shaft 122 which can be adjusted bya threaded mechanism 128. The maximum excursion of the drive shaft 108is limited by a pin 130 extending from the drive shaft 108 and a pair oflimit switches 132.

The magnetic force applied is sufficient to advance the palpation probe92 to compress the tissue under investigation but not enough to causediscomfort or damage to the tissue. The time and distance the probeadvances will be in proportion to the density of the tissue, resultingin less time and movement for dense tissue and more time and movementfor less dense tissue.

In operation, a first coil 118 is actuated to move the palpation probe92 a predetermined force, distance, time, or some combination thereof.The first coil 118 is energized in a step-wise fashion at about 250 mvincrements from 0 to 10 volts, and the change in force is about 10 gramsper mm² per step. When the probe fails to move a predetermined distancefor a predetermined time, additional force is applied by means of asecond coil 118. It is to be understood that additional coils similarlyoperated, can be added as required.

The resistance characteristic of the tissue under investigation isdetermined when the applied pressure, distance traveled or time ofpressure reaches a predetermined value. The parameters of force,distance or time are measured at the predetermined value and theparameter information is then transferred to information storage meansand/or to a controller for processing, analysis, and the production ofmulti-dimensional images.

In one aspect of the invention, the palpation information including, butnot limited to, distance, force, time, resistance, and characteristicvalue of the tissue under investigation, are obtained by encoding andtransmitting the acquired palpation information. As shown in FIG. 4, alaser optic card 124 associated with the shaft 108 is read by a lasercard reader 126 which transmits the encoded information to a storagedevice or the controller 17 for processing. The controller thenprocesses the information as required for use by other devices or in amanner similar to CAT systems or equivalent devices.

An example of a laser card 124 that is to be used with the laser cardreader 126 is shown in FIG. 4 a. The card 124 has a series of reflectingareas 129 that are separated by non-reflective areas 131. Thenon-reflecting areas 131 of the card 124 can be light absorbing ortransparent. A laser transmitter 133 directs a laser beam 135 againstthe patterned area of the laser card 124. When the laser beam 135 hits areflecting area, reflected light is picked up by a receiver 137. As thecard 124 is moved in a direction transverse to the reader 126, thepattern of reflected pulses are counted to measure movement of the driveshaft 108 and the palpation probe 92. The reflecting areas can be assmall as about 0.001 mm for more precise measurements of the motion ofthe palpation probe 92. Although only laser illumination has beendiscussed, it is to be understood that any form of illumination can beapplied including, but not limited to, visible, infrared, or ultravioletlight, which may, or may not, be coherent, focused, columnated ordiffused.

Palpation Actuators and Probes

In another aspect of the invention, a palpation detector for detectingchanges in density of tissue is shown in FIG. 7. A permanent magnet 200is mounted on a non-magnetic rod 202 that is movable along the axis ofthe rod centerline. Suitable guides 204 such as rollers, ball bearings,a sleeve or the like are provided for smooth, low resistance, axialmovement of the rod 202. The permanent magnet 200 is proximate to anelectromagnetic coil head 206 mounted on a shaft 207 and fixed to ahousing 208. The permanent magnet 200 and the electromagnet head 206have common poles while the rod 202 has an opposing pole 210.Electromagnet head 206 is powered by any suitable number of poweredcoils 212 that are connected at a terminal 214 to a power source bysupply wires 216. The magnets 200, 206 having common poles will opposeeach other pushing the magnets 200, 206 apart when the electromagnetcoils 212 are activated. The intensity of the opposing force is adjustedby the number of coils 212 and the level of power applied thereto.

A palpation probe tip 218 is shown in FIG. 11, according to the presentinvention The palpation probe tip 218 is mounted on the distal end ofthe rod 202 which is brought into contact with (or to a predetermineddistance from) the tissue under investigation, such as a breast surfaceby the carriage 11. The coil 212 is energized to increase the fieldaround a shaft 207 to increase the field at the electromagnetic head 206in order to force the permanent magnet 200 further away from theelectromagnetic head 206, which moves the palpation probe tip 218against the tissue. The tissue is depressed at the point of contactwhich transfers the tissue's elasticity characteristic in the form of aback pressure through the probe tip 218 and rod 202 toward the coil head206.

The amount of back pressure applied including variations thereof aremeasured by recording instrumentation associated with the processor 17.It is to be understood that this pressure measurement system can beincorporated with any palpation device disclosed herein. Additionalembodiments of palpation detection and actuator devices are shown inFIGS. 8-14.

The detection and actuator device shown in FIG. 8 includes a permanentmagnet 222 that is mounted at one end to an actuator rod 224 which issupported by a slidable sleeve 226 that is mounted on a housing 228. Atip 218 of the sort shown in FIG. 11 is secured to the other end of rod224. A second permanent magnet 230 is mounted on a holder 231 that iscoaxial with the rod 224. The permanent magnets 222, 230 are selectedwith common poles (north to north or south to south.) The holder 231 issupported on a disk 232 that is slidable within the housing 234 andcoaxial with the rod 224. A sleeve 236 is preferably mounted on theholder 231 to aid in guiding the movement of the rod 224.

FIG. 11 shows a preferred embodiment of a palpation tip configuration218. The tip configuration 218 includes a rounded endpiece 254 forcontact with the tissue under investigation. Any suitable material maybe used that can be inexpensively cleaned and made safely disposable ispreferred. An end isolator 256, made up of an electrically insulatingmaterial is used to prevent static electricity discharge of the tissue.A core member 258 connects the endpiece 254 to a base 260 which issecured in any suitable manner, such as threads, to the rod 224.

In operation, the detector 14 is moved as discussed above to bring thepalpation tip 218 into proximity with a selected location along thetissue under investigation. When the palpation tip 218 is initiallybrought into proximity to the breast surface, gravity causes the rod 224and the permanent magnets 222 to move apart. A motor 238 mounted in ahousing 234 drives a lead screw 240 which is threaded through acorresponding female thread 241 in a disk 232. The motor 238 may be anysuitable motor, such as a low rpm DC motor or a stepper motor. Rotationof the lead screw 240 will move magnet 230 towards magnet 222 decreasingthe intermagnet gap until the tissue resistance returns the intermagnetgap to a predetermined distance. The displacement of the holder 231 andthe disk 232 is related to the tissue density characteristics of thetissue at the contact point. A sensor 242 counts the revolutions of themotor 238 to measure the corresponding degree of movement of thepalpation tip 218 into the tissue.

Conventional safety sensors 244 may be provided to limit maximummovement of disk 232 (and movement of tip 218 in accordance with diskposition) to prevent damage to the breast As mentioned above, themagnetic field between the magnets 222, 230 will act as a resilientmount for the palpation probe tip 218, limiting any damage or injuryshould the tip strike a breast or other surface.

FIG. 9 shows another embodiment of a detector 14 having a pair ofhousings 228, 234, an actuator rod 224, sleeves 226, 236, a palpationtip 218, a holder 231, a disk 232, a motor 238, and sensors 242, 244.Instead of spaced permanent magnets 222, 230 a spring 248 is fastenedbetween the proximal end of the rod 224 and the holder 231. The spring248 is selected to provide a bias to the two juxtaposed ends of the rod224 and the holder 231 to a particular, predetermined spacing. When thedetector 14 is positioned over the tissue the palpation tip 218 extendsdownwardly under the force of gravity. The motor 238 rotates to move thedisk 232 and holder 231 toward the rod 224 until the gap between thedistal end of the holder 231 and the proximal end of the rod 224 is atthe original predetermined distance. The total movement of the holder231 is indicated by the number of revolutions of the lead screw 240 asmeasured by the counting sensor 242, which is indicative of the desiredtissue characteristic.

Another aspect of a detector 14 is shown in FIG. 10 having a gas 250interface that is enclosed within a sleeve 236 at the proximal end of arod 224. The sleeve 236 fits over the rod 224 in a sealing arrangementto prevent the pressurized gas 250 from escaping. Any suitableconventional seals may be used between the rod 224 and the sleeve 236.

The axial force applied to the rod 224 will change the gas pressurewithin the sleeve 236 which will be measured by a pressure sensor. Whenplaced in contact with the tissue under investigation, the contactpressure is sensed 252 by the amount of pressure applied to the gas bythe palpation probe 218. Pressure in the sleeve is adjusted by therotation of the motor 238 which is counted by sensor 242. The amount ofpressure applied by the rotation of the motor 238 is proportional to thedesired tissue characteristic such as hardness and density.

FIG. 12 shows another detector 14 having a plurality of palpation probetips 218 that are arranged in a parallel array and mounted on acorresponding number of actuator rods 262 for axial movement. In oneaspect of the detector 14, a plurality of offset extension connectors264 made of inflexible cables are used to transmit motion by means oftransducers 266 that are connected to the output ends of the rods 262.An optical encoder and reader system 268 is incorporated to measure themovement of each palpation tip 218 during palpation of the tissue underinvestigation.

FIGS. 13 a and 13 b show two embodiments of the encoder and readersystem 268 having a plurality of detectors 276 and encoder cards(strips) 272. The encoder system 268 includes an encoder slide 270 thatis secured to the rod 224. The encoder slide 270 is secured to anysuitable part of the rod 224 or to the palpation tip 218, as desired.The encoder slide 270 is transparent and includes a strip 272 withreflective dots 274 (or, in the alternative transparent dots in anotherwise opaque strip 272).

Decoder sensors 276 mounted on a housing 278 are provided on oppositesides of the encoder slide 270 and secured to the housing 278 by anysuitable mounting means. The decoder sensors 276 are optical or lasersensors having light emitters of the sort used to read compact disks.The dots 274 are reflective particularly against a transparentbackground which causes light to pass between the pair of lighttransmitting decoder sensors 276. As the encoder slide 270 is moved,light from the emitters is either reflected by the reflective dots 274or transmitted through the disk and onto the opposite sensor 276.

Accordingly, the detected light indicates movement of the slide and thenumber of pulses of light received which are used to measure thedistance of movement of the rod 224 and the palpation tip 218.Altematively, when the dots 274 are transparent against an opaquebackground, light pulses received at the detector decoder sensor 276will indicate the distance of movement of the rod 224 and the palpationtip 218. FIG. 14 shows another embodiment of the detector 14 in whichthe optical locating head 16 and detector 14 are both mounted at the endof the arm 61 on carriage 11.

FIG. 15 shows and optical locator 16 having a motor housing 282 incombination with a detector 16. A lens enclosure 284 is secured to themotor housing 282 after precise positioning during manufacture of theassembly. A lens assembly 286 is slidably mounted within lens enclosure284 for axial movement relative thereto. A motor 288 is mounted withinthe motor housing 282 and drives a lead screw 290 which is threadedthrough a nut 292 secured to lens assembly 286 to move the lens assembly286 axially within lens enclosure 284.

Two laser beam positioning enclosures 294 are mounted on opposite sidesof motor housing 282. Each enclosure 294 contains a pre-focusedconventional (typically 680 to 850 nanometer) laser diode and lightsensor 296. A prism 297 refracts light from a laser diode of the lightsensor 296 toward the tissue being examined. Light reflected from thetissue surface passes back through the prism 297 to the sensor 296. Thesensed returned light will be at a maximum when the beam from the beamgenerated by the sensor 296 is 90° incident to the tissue surface. Themechanism described above for moving a palpation tip 218 in threedimensions can thus adjust the tip orientation to provide palpation at90° to the breast surface.

A motor 300 in each laser beam positioning enclosure 294 drives a leadscrew 302 that engages an arcuate gear sector 304 to rotate each sensor296 and prism 297 about the center of rotation of gear sector 304. Thelaser diode within sensor 296 generates a laser beam that produces a reddot on the tissue being examined. A conventional sensor 306 within eachenclosure 294 counts rotation of the lead screw 302 and is calibrated toindicate the exact distance to the surface upon which the dot appearswhen the beam is at 90° to the surface. The system computer then canconventionally calculate a three dimensional image of the tissue surfacefrom a number of these angle readings.

Lens assembly 286, in conjunction with a light sensor 308, a pre-focusedsensor lens 310 and lenses 312 operate in the same manner as a cameraautomatic focusing systems to bring the tissue surface into sharpoptical focus by rotating the lead screw 290 as necessary. A positionsensor 313 counts rotation of the lead screw 290 to provide positioninformation to the processor 17 or some other system such as a computer.As the optical locator 16 moves and focuses on the tissue, the palpationdetector 14 is brought into contact with the tissue surface.

Extreme position sensors 314 are preferably provided to sense movementof the lens enclosure 284 to the ends of its desired range of movementand prevent damage which might be caused by movement outside theselected range. Sensors 314 may be conventional sensors, such aselectro-optical or pressure switches, which can turn off motor 288.

Multi-dimensional Mapping

In operation, either of the locator 16 embodiments shown in FIGS. 5 and15 can be conventionally programmed to map an entire breast andassociated tissue step by step. The horizontal and vertical (X and Y)movements of the robot arm (carriage) 11 position the location device 16at selected points across the tissue under investigation. The focusingmechanism within the motor housing 282 and the lens enclosure 284continually focus the sensor 308 to provide the necessary Z directionalignment. The position sensor 313 will count the revolution of themotor 288 while the motor brings the lens assembly 286 to the point offocus to continuously provide lens position information.

Once the locator 16 has visited all desired points of the tissue and acalculation is made of the distance from every desired point, theprocessor 17 generates a multi-dimensional image (two or threedimensions) of the tissue under investigation.

For example, during palpation of a breast, the locator 16 verifies thelocation being palpated and can automatically compensate for breastmovement as the patient breathes. In addition, a map of the breast isproduced by a video camera 316 mounted with the locator 16 as shown inFIG. 14. Other types of mapping can be produced using the distancetraveled by the palpation probe 92, the velocity of travel of thepalpation probe 92, and the time of palpation at each contact point. Forexample, velocity data may be used, preferably in conjunction with thedistance traveled and time data, to calculate the breast tissue densityat each palpation point. Thus, the apparatus of this invention willprovide an accurate map of the breast as well as detect tissue densityanomalies, and provide the ability to accurately reexamine the breastfrom time to time to monitor any changes in breast density anomalies.

Sampling Devices

In addition, referring to the alternative embodiments illustrated inFIGS. 16 and 17, a sampling device 400 is provided to further examinethe identified regions of tissue density anomalies in order to determinethe predetermined tissue characteristics and regions such as, but notlimited to, skin, fat, muscle, and abnormal tissue such as cancer. Thesampling device 400 is connected to a detector 14 that is incommunication with the processor 17. The sampling device 400 may be aninvasive or non-invasive device 402, such as but not limited to aneedle, aspirator, coring device, ultrasound device, temperature device,electromagnetic sensing device, impedance measurement device, or somecombination thereof The sampling device 400 is positioned by theprocessor 17 at predetermined locations of the tissue underinvestigation By means of three dimensional mapping produced from thetissue density data, the sampling devices may be more effectivelyemployed to obtain additional data or even tissue samples from thetissue under investigation.

Other examples of sampling devices that may be incorporated with theinvention are shown in FIGS. 18 a-18 c and include a biopsy needle andanesthetic delivery device 406, a multi-electrode sensor array 404 forexamining detected tissue anomalies, a T-Scan 2000 manufactured byTransScan Research and Development Ltd. for detecting low-level electriccurrents and impedance to produce a real-time image of the electricaldistribution within the breast, an ultrasound device, a temperaturemeasuring device, or a liposuction device 408.

A Dynamic Color Imaging System

The present invention includes a color density imaging system capable ofdisplaying images of tissue characteristics, in real time, detected anddetermined by the apparatus described above, or by other apparatuscapable of providing tissue characteristics. The controller 17 of theapparatus 10 includes software that receives, stores and processes datadetected by the apparatus, then transmits to a monitor color images ofthe tissue characteristics. The colors displayed in the image correspondto certain values of a predetermined tissue characteristic, orcharacteristics, for tissue displayed in the image. The data collectedby the apparatus 10 can be in any standard bit format, depending uponthe operating settings of the individual components of the apparatus 10.

The apparatus 10 collects four sets of data. The data is recorded into adesignated file in the controller 17 and processed by the software tocreate the color image. The detector (or detection head) 14 collectsdata related to tissue characteristics. The locator (or location head)16 collects data related to X and Y dimensions of the patient 68relative to the location pattern 71 of the matrix board 66 and datarelated to the X and Y dimensions of the detection head 14 relative totissue of the patient 68 and to the location pattern 71. The opticalhead (light source with focusing lenses or laser location device) of thelocator 16 collects data related to the height (or Z dimension) of thedetection head 14 relative to the tissue of the patient 68. The camera134, 316 provides an initial image of the tissue of the patient 68 andcollects data related to the X and Y dimensions of the tissue relativeto the created image.

The software receives, processes and transmits for display an initialimage of the tissue under investigation as provided by the camera 134,316, dividing the image into predetermined portions. Associated witheach portion of the image is data describing a first and a secondcoordinate of the tissue relative to the patient 68. The initial imageis processed in one of any of a number of formats, depending on theoperating system employed (e.g., a bit map:.bmp). The predeterminedportions of the image could relate to individual pixels of the monitoror screen displaying the color image.

The software receives characteristic data of the tissue from thedetection head 14 for each portion of the image. Data received from thelocation head 16 monitors the position of the detection head 14 relativeto the tissue under investigation and associates the location of thedetection head 14 (and characteristic data resulting therefrom) to eachportion of the displayed image. Data collected from the optical headmonitors the height (or Z dimension) of the detection head 14 relativeto the tissue under investigation to associate the location of thedetection head (and characteristic data resulting therefrom) with the Zdimension (or depth) of the tissue under investigation for use inrecording characteristic data in three-dimensions and for creating(displaying) three-dimensional images of tissue characteristics.

The software associates (or assigns) a color, or shade thereof, tovarious incremental values of the characteristic data for each portionof the displayed image. The association of color to incremental valuesof characteristic data can be accomplished by first assigning a certaincode to each incremental value of characteristic data. The software isprogrammed to then associate a particular color to every code. The colordisplayed for each portion of the image, therefore, results from thesoftware determining a code for each portion of the image based upon theparticular value of the characteristic data and then associating a colorto the resultant code. Including code assignments in the colorassociation process is especially useful when the characteristic datareceived and processed for color imaging includes data determined foreach of a plurality of properties. Each property is assigned a set ofcodes and a certain code within the set is assigned to the propertydepending upon the incremental value determined for that property by thedetection head 14. A resultant code (for each portion of the image) isthen calculated based upon a formula that considers the certain codeassigned for each property, and the number of properties included in thecharacteristic data. The formula may be weighted, giving greaterconsideration to one or more particular properties, or to particularcodes within each property. The software then proceeds to associate acolor to the resultant code for each portion of the image.

In one embodiment of the invention, the characteristic data includesjust one property: tissue density. Tissue density is determined bysoftware which processes data collected by the detection head 14 relatedto distance traveled by the palpation probe 218, velocity of travel ofthe palpation probe 218 and a time of palpation at each palpation probecontact point with tissue. However, the characteristic data could be anyproperty, or a combination of properties selected from the groupconsisting of tissue density, tissue temperature, tissue color, tissueresistance, tissue conductivity, tissue impedance, tissue ultrasoundresults and tissue sampling results. In addition, the data collected bythe detection head 14 to determine tissue density could also becharacteristic data (i.e., any one or combination of properties relatedto palpation probe 218 information, such as distance traveled by thepalpation probe 218, velocity of travel of the palpation probe 218 and atime of palpation at each contact point (for each portion of the image).

In another embodiment of the invention, a specific area of the tissueunder investigation (defined by X and Y coordinates) has characteristicdata determined, processed, recorded and displayed for each portion ofthe image and for each portion of the image for each of a plurality oflevels (or layers in Z dimension). The optical head of the locationdevice 16, in conjunction with the detection head 14, allow for themultiple level processing of characteristic data in three-dimensions.Due to the two-dimensional limitations of typical computer monitors ordisplay screens, multiple color images are processed and displayed for aparticular X and Y coordinate of tissue under investigation, one imagefor each level (or incremental Z coordinate value). The images relatingto incremental levels (or layers) of tissue depth can be scrolledthrough, one by one, for the particular X and Y coordinates of tissueunder investigation.

In another embodiment of the invention, secondary software processes anddisplays the multiple image layers, one over another in right sequentialorder, to create a virtal three-dimensional image for aparticular X andY coordinate of the tissue under investigation. The three-dimensionalimage allows an analyst to easily and expeditiously determine theexistence and location of tissue anomalies in three-dimensions.

In another embodiment of the invention, the virtual three-dimensionalimage for a particular X and Y coordinate of the tissue displays acolor, for each portion of the image, that considers the value of thecharacteristic data for each level (or Z dimension) simultaneouslydisplayed for the respective portion (X and Y coordinate) of the image.The software includes a formula that considers the value of thecharacteristic data for each level simultaneously displayed for eachportion of the image. The formula can be weighted, giving greaterconsideration to the value of characteristic data of levels in closerproximity to the level displayed by the three-dimensional image.

A color image having uniform color throughout the image (i.e., uniformcolor from portion to portion over the image) represents tissue havingsimilar, or nearly similar, characteristic data for the entire area oftissue displayed. A variation of color from portion to portion over thetwo or three-dimensional color image signifies that the characteristicdata of tissue also vary from portion to portion over the tissue underinvestigation. For example, if the characteristic data is tissuedensity, and the palpation probe 218 of the detection head 14 collectsdata relating to a tissue abnormality (i.e., a high density mass) at aparticular tissue location, the color of the corresponding tissuelocation on the image will vary relative to the color displayed at otherportions of the image. The degree of color variation, from portion toportion over the image, will depend on the degree of density variationfrom portion to portion over the tissue under investigation.

Naturally, different areas of tissue may inherently have differentcharacteristic data, and such would be displayed by the color image. Forexample, if the color image displays breast tissue and thecharacteristic data is tissue density, the nipple area of the breastwould be displayed with color differing from that displayed for otherbreast areas.

In another embodiment of the invention, the software calculates, recordsand provides, on command, the size of tissue defined by a certain,predetermined characteristic value. These calculations of size can be intwo or three dimensions. Associated with this calculation andrecordation is the coordinate location information of the respectivemass relative to the tissue. This information is stored for further,comparative analysis at subsequent tissue examinations. Thetwo-dimensional and/or three dimensional color images are also stored(along with the location of the tissue displayed relative to thepatient) for comparative analysis at subsequent examinations.

In another embodiment of the invention, the system processes recordedinformation related to characteristic data of tissue determined forselected first, second and third coordinates of tissue relative to asubject body and programmably compares the characteristic data withpreviously (i.e., at a previous examination) determined characteristicdata related to the same first, second and third coordinates of tissuerelative to the same subject body. The system displays an image of theselected first, second and third coordinates of the tissue underinvestigation, and color is assigned to each portion of the image basedupon a formula that calculates any change, and degree thereof, in thecharacteristic data for that portion of the image. A pre-determinedcolor is associated with certain incremental values of change in thecharacteristic data (i.e., change in characteristic data betweenselected examinations) for each portion of the image. The color imageprovides a quick and accurate means to determine the existence, locationand degree of change, over time, in selected characteristic data for anythree-dimensional region of tissue.

In another embodiment of the invention, the changes in thecharacteristic data between different examination events, calculated foreach portion of the image, are directed to a difference, in absolutevalue, of the respective characteristic data. The changes calculated,however, could be directed to a first derivative analysis of therespective characteristic data compared, for each portion of the image.Or, the changes calculated could incorporate both, using a formula thatconsiders both the change in absolute value between the characteristicvalue of two examination events and the first derivative analysis of thecharacteristic value, for each portion of the image.

In another embodiment of the invention, the formula is weighted, givinggreater consideration to either the change in absolute value or thefirst derivative analysis. The formula, in one embodiment, is weighteddepending on the specific portion of the image under investigation. Forinstance, the formula might heavily weigh the first derivative analysisfor portions of the image displaying the perimeter of a suspect mass,and heavily weigh the change in absolute value for interior portions ofthe suspect mass and for tissue of otherwise normal characteristicvalue. In this scenario, the color image portraying change betterdetails and more accurately displays a change in a suspect mass, overtime, by focussing on the change in characteristic data relative toneighboring, normal tissue (through use of the first derivativeanalysis) for perimeter areas of the suspect mass, and by focussing onthe change in absolute value for interior portions of the suspect massand for tissue of otherwise normal characteristic value (through use ofthe change in absolute value) so that the image is not empty, or void,in those portions.

While certain specific relationships, materials and other parametershave been detailed in the above description of embodiments, these can bevaried, where suitable, with similar results. In particular, applicationto assess and image other parts of the body is possible, such as, butnot limited to, the face, abdomen, thighs, buttocks, etc. In theseregions as well as the breast, the method and system of the presentinvention may be used for the imaging of subcutaneous fat. In addition,the present invention may assess, image, and track the cancerous stateof skin lesions. Furthermore, all of the above could be applied to othermammals.

These and other advantages of the present invention will be apparent tothose skilled in the art from the foregoing specification. Accordingly,it will be recognized by those skilled in the art that changes ormodifications may be made to the above-described embodiments withoutdeparting from the broad inventive concepts of the invention. It shouldtherefore be understood that this invention is not limited to theparticular embodiments described herein, but is intended to include allchanges and modifications that are within the scope and spirit of theinvention as set forth in the claims.

1. A method for imaging tissue characteristics, comprising the steps of:a. developing an image of tissue, the image divided into pre-determinedportions and accompanied by data describing a first and a secondcoordinate of the tissue relative to a subject body for each portion ofthe image; b. receiving characteristic data of the tissue for eachportion of the image, each portion of the image having a first and asecond coordinate relative to the image; c. associating a color to thecharacteristic data for each portion of the image; and d. displaying thecolor for each portion of the image, whereby differing colors displayedover the image assist in determining the existence of tissue anomaliesin the subject body.
 2. The method of claim 1, wherein each portion ofthe image is a pixel.
 3. The method of claim 1, wherein thecharacteristic data is density.
 4. The method of claim 1, furtherincluding the step of calculating and recording a size for tissue ofpredetermined characteristic value.
 5. The method of claim 1, whereinthe image of tissue is received from a camera.
 6. The method of claim 1,wherein the data describing the first and the second coordinate of thetissue relative to a subject body is received from a camera.
 7. Themethod of claim 1, wherein the characteristic data of the tissue isreceived from a palpation device.
 8. The method of claim 1, wherein alocation head provides positional data associating the characteristicdata detected by the palpation device with the portion of the imagerelating to the first and the second coordinate of the tissue detected.9. The method of claim 1, wherein the characteristic data is selectedfrom the group consisting of tissue density, temperature, color,resistance, conductivity, impedance, ultrasound and samplinginformation.
 10. The method of claim 1, wherein the characteristic datais selected from the group consisting of a distance traveled by apalpation probe, a velocity of travel of the palpation probe and a timeof palpation at each contact point.
 11. The method of claim 1, furthercomprising the step of receiving characteristic data of the tissue foreach portion of the image for each of a plurality of third coordinatevalues and data describing the respective third coordinate value of thetissue relative to the subject body for each portion of the image. 12.The method of claim 11, wherein multiple image layers can be displayed,each image layer corresponding to a different incremental thirdcoordinate value of the tissue relative to the subject body, eachrespective portion of the multiple image layers having similar first andsecond coordinates of the tissue relative to the subject body.
 13. Themethod of claim 12, wherein the multiple image layers are displayedsimultaneously, one over another, to create a virtual, three-dimensionalimage, whereby locating, in three-dimensions, tissue anomalies withinthe subject body is possible through inspection of the three-dimensionalcolor image.
 14. The method of claim 13, wherein the color displayed foreach portion of the three-dimensional image is selected based on aformula that considers the characteristic data of the tissue for eachlayer simultaneously displayed for that respective portion.
 15. Themethod of claim 14, wherein the formula is weighted, giving greaterconsideration to the characteristic data of the tissue for layers incloser proximity to the layer displayed by the three-dimensional image.16. The method of claim 11, further including the step of calculatingand recording a three-dimensional size for tissue of pre-determinedcharacteristic value.
 17. A method for imaging tissue characteristics,comprising the steps of: a. developing an image of tissue, the imagedivided into pre-determined portions and accompanied by data describinga first and a second coordinate of the tissue relative to a subject bodyfor each portion of the image; b. receiving characteristic data of thetissue for each portion of the image, each portion of the image having afirst and a second coordinate relative to the image; c. associating acode to the characteristic data for each portion of the image; d.associating a color to each code; and e. displaying the color for eachportion of the image, whereby differing colors displayed over the imageassist in determining the existence of tissue anomalies.
 18. The methodof claim 17, wherein each portion of the image is a pixel.
 19. Themethod of claim 17, further including the step of calculating andrecording a size for tissue of pre-determined characteristic value. 20.The method of claim 17, wherein the characteristic data includes datadetermined for each of a plurality of properties.
 21. The method ofclaim 20, wherein a different set of codes is assigned to each of theplurality of properties.
 22. The method of claim 21, wherein associatinga color to each code associates a color to a resultant code, theresultant code calculated based on a formula that considers each of theplurality of properties and a respective value of the data determinedfor each property.
 23. The method of claim 22, wherein the formulaprovides a pre-determined weight for each property and for therespective value of the data determined for each property.
 24. Themethod of claim 17, wherein the characteristic data is density.
 25. Themethod of claim 17, wherein the characteristic data is selected from thegroup consisting of tissue density, temperature, color, resistance,conductivity, impedance, ultrasound and sampling information.
 26. Themethod of claim 17, wherein the characteristic data is selected from thegroup consisting of a distance traveled by a palpation probe, a velocityof travel of the palpation probe and a time of palpation at each contactpoint.
 27. The method of claim 17, further comprising the step ofreceiving characteristic data of the tissue for each portion of theimage for each of a plurality of third coordinate values and datadescribing the respective third coordinate value of the tissue relativeto the subject body for each portion of the image.
 28. The method ofclaim 27, wherein multiple image layers can be displayed, each imagelayer corresponding to a different incremental third coordinate value ofthe tissue relative to the subject body, each respective portion of themultiple image layers having similar first and second coordinates of thetissue relative to the subject body.
 29. The method of claim 28, whereinthe multiple image layers are displayed simultaneously, one overanother, to create a virtual, three-dimensional image, whereby locating,in three-dimensions, tissue anomalies within the subject body ispossible through inspection of the three-dimensional color image. 30.The method of claim 29, wherein the color displayed for each portion ofthe three-dimensional image is selected based on a formula thatconsiders the characteristic data of the tissue for each layersimultaneously displayed for that respective portion.
 31. The method ofclaim 30, wherein the formula is weighted, giving greater considerationto the characteristic data of the tissue for layers in closer proximityto the layer displayed by the three-dimensional image.
 32. The method ofclaim 27, further including the step of calculating and recording athree-dimensional size for tissue of pre-determined characteristicvalue.
 33. A method for creating color images of tissue density,comprising the steps of: a. developing an image of tissue, the imagedivided into predetermined portions and accompanied by data describing afirst and a second coordinate of the tissue relative to a subject bodyfor each portion of the image; b. receiving a density value of thetissue for each portion of the image, each portion of the image having afirst and a second coordinate relative to the image; c. associating acolor to the density value for each portion of the image; and d.displaying the color for each portion of the image, whereby differentcolors displayed over the image relate to different densities of tissueand thereby assist in determining the existence of tissue anomalies. 34.A method for creating three-dimensional color images of tissue density,comprising the steps of: a. developing an image of tissue, the imagedivided into pre-determined portions and accompanied by data describinga first and a second coordinate of the tissue relative to a subject bodyfor each portion of the image; b. receiving a density value of thetissue for each portion of the image, each portion of the image having afirst and a second coordinate relative to the image; c. receiving adensity value of the tissue for each portion of the image for each of aplurality of third coordinate values and data describing the respectivethird coordinate value of the tissue relative to the subject body foreach portion of the image; d. assigning a color for each portion of theimage, the color assignment based on a formula that considers thedensity value of the tissue for each respective third coordinate value;and e. displaying the color for each portion of the image, wherebydifferent colors displayed over the image relate to different densitiesof tissue in three-dimensions, thereby assisting in determining theexistence of tissue anomalies within the subject body.
 35. The method ofclaim 34, wherein the formula is weighted, giving greater considerationto the density value of the tissue for third coordinate values in closerproximity to the third coordinate value displayed by thethree-dimensional image.
 36. The method of claim 34, further includingthe step of calculating and recording a three-dimensional size fortissue of pre-determined characteristic value.
 37. A method for creatingcolor images displaying tissue characteristics, comprising the steps of:a. developing an image of tissue, the image divided into pre-determinedportions and accompanied by data describing a first and a secondcoordinate of the tissue relative to a subject body for each portion ofthe image; b. receiving characteristic data of the tissue for eachportion of the image, wherein the characteristic data includes detectedvalues for a plurality of properties; c. determining a resultant codefor the characteristic data, wherein a set of codes is associated witheach property, a certain code within the set is associated with thedetected value of the respective property, and the resultant code iscalculated using a formula that considers each detected value and eachproperty; d. associating a color to each resultant code; and e.displaying the color for each portion of the image, whereby differingcolors displayed over the image assist in determining the existence andlocation of tissue anomalies.
 38. A method for creatingthree-dimensional color images displaying tissue characteristics,comprising the steps of: a. developing an image of tissue, the imagedivided into pre-determined portions and accompanied by data describinga first and a second coordinate of the tissue relative to a subject bodyfor each portion of the image; b. receiving characteristic data of thetissue for each portion of the image and for each portion of the imagefor each of a plurality of levels, wherein the characteristic dataincludes detected values for a plurality of properties; c. determining aresultant code for the characteristic data for each portion of the imageand for each portion of the image for each of a plurality of levels,wherein a set of codes is associated with each property, a certain codewithin the set is associated with the detected value of the respectiveproperty, and the resultant code is calculated using a formula thatconsiders each detected value and each property; d. assigning a colorfor each portion of the image, the color assignment based on a weightedformula that considers the resultant code for each of the plurality oflevels for the respective portion of the image, the weighted formulagiving greater consideration to the resultant code for respective levelsin closer proximity to the level in the image; and e. displaying thecolor for each portion of the image, whereby differing colors displayedover the image assist in determining the existence and location oftissue anomalies in three dimensions.
 39. A method of displaying changesin tissue characteristics, over time, by color image, comprising thesteps of: a. developing an image of tissue, the image divided intopre-determined portions and accompanied by data describing coordinatesof the tissue relative to a subject body for each portion of the image;b. receiving characteristic data of the tissue for each portion of theimage for separate instances in time, each portion of the image having afirst and a second coordinate relative to the image; c. determining avalue of a difference in the characteristic data of the tissue for eachportion of the image for the separate instances in time; d. associatinga color to the value of the difference in the characteristic data foreach portion of the image; and e. displaying the color for each portionof the image, whereby differing colors displayed over the image assistin determining the existence and location of changes in tissuecharacteristics over time for the subject body.
 40. The method of claim39, wherein determining the value of the difference in thecharacteristic data of the tissue for each portion of the image for theseparate instances in time is based upon a formula that calculates thedifference in the characteristic data for the separate instances intime, and degree thereof, for each portion of the image.
 41. The methodof claim 40, wherein associating a color to the value of the differenceis based upon having a pre-determined color assigned to certainincremental values of difference in the characteristic data, whereby thecolor image provides a quick and accurate means to determine theexistence, location and degree of difference, over time, incharacteristic data of tissue for the subject body.
 42. The method ofclaim 40, wherein the formula considers both a difference, in absolutevalue, of the characteristic data and a first derivative analysis of thecharacteristic data.
 43. The method of claim 42, wherein the formula isweighted depending on the portion of the image, the formula givinggreater weight to the first derivative analysis for portions of theimage displaying a perimeter of a suspect mass and giving greater weightto the difference in absolute value of the characteristic data forinterior portions of the suspect mass and for tissue of normalcharacteristic value.
 44. The method of claim 39, wherein determiningthe value of the difference in the characteristic data relates to eitherdetermining a difference, in absolute value, of the characteristic dataor to a first derivative analysis of the characteristic data.
 45. Acomputer-readable medium that con figures a computer system to perform amethod for imaging tissue characteristics, the method comprising thesteps of: a. developing an image of tissue, the image divided intopre-determined portions and accompanied by data describing a first and asecond coordinate of the tissue relative to a subject body for eachportion of the image; b. receiving characteristic data of the tissue foreach portion of the image, each portion of the image having a first anda second coordinate relative to the image; c. associating a color to thecharacteristic data for each portion of the image; and d. displaying thecolor for each portion of the image, whereby differing colors displayedover the image assist in determining the existence of tissue anomaliesin the subject body.
 46. A computer-readable medium that configures acomputer system to perform a method for imaging tissue characteristics,the method comprising the steps of: a. developing an image of tissue,the image divided into pre-determined portions and accompanied by datadescribing a first and a second coordinate of the tissue relative to asubject body for each portion of the image; b. receiving characteristicdata of the tissue for each portion of the image, each portion of theimage having a first and a second coordinate relative to the image; c.associating a code to the characteristic data for each portion of theimage; d. associating a color to each code; and e. displaying the colorfor each portion of the image, whereby differing colors displayed overthe image assist in determining the existence of tissue anomalies.
 47. Acomputer-readable medium that configures a computer system to perform amethod for creating color images of tissue density, the methodcomprising the steps of: a. developing an image of tissue, the imagedivided into pre-determined portions and accompanied by data describinga first and a second coordinate of the tissue relative to a subject bodyfor each portion of the image; b. receiving a density value of thetissue for each portion of the image, each portion of the image having afirst and a second coordinate relative to the image; c. associating acolor to the density value for each portion of the image; and d.displaying the color for each portion of the image, whereby differentcolors displayed over the image relate to different densities of tissueand thereby assist in determining the existence of tissue anomalies. 48.A computer-readable medium that configures a computer system to performa method for creating three-dimensional color images of tissue density,the method comprising the steps of: a. developing an image of tissue,the image divided into pre-determined portions and accompanied by datadescribing a first and a second coordinate of the tissue relative to asubject body for each portion of the image; b. receiving a density valueof the tissue for each portion of the image, each portion of the imagehaving a first and a second coordinate relative to the image; c.receiving a density value of the tissue for each portion of the imagefor each of a plurality of third coordinate values and data describingthe respective third coordinate value of the tissue relative to thesubject body for each portion of the image; d. assigning a color foreach portion of the image, the color assignment based on a formula thatconsiders the density value of the tissue for each respective thirdcoordinate value; and e. displaying the color for each portion of theimage, whereby different colors displayed over the image relate todifferent densities of tissue in three-dimensions, thereby assisting indetermining the existence of tissue anomalies within the subject body.49. A computer-readable medium that configures a computer system toperform a method for creating color images displaying tissuecharacteristics, the method comprising the steps of: a. developing animage of tissue, the image divided into pre-determined portions andaccompanied by data describing a first and a second coordinate of thetissue relative to a subject body for each portion of the image; b.receiving characteristic data of the tissue for each portion of theimage, wherein the characteristic data includes detected values for aplurality of properties; c. determining a resultant code for thecharacteristic data, wherein a set of codes is associated with eachproperty, a certain code within the set is associated with the detectedvalue of the respective property, and the resultant code is calculatedusing a formula that considers each detected value and each property; d.associating a color to each resultant code; and e. displaying the colorfor each portion of the image, whereby differing colors displayed overthe image assist in determining the existence and location of tissueanomalies.
 50. A computer-readable medium that configures a computersystem to perform a method for creating three-dimensional color imagesdisplaying tissue characteristics, the method comprising the steps of:a. developing an image of tissue, the image divided into pre-determinedportions and accompanied by data describing a first and a secondcoordinate of the tissue relative to a subject body for each portion ofthe image; b. receiving characteristic data of the tissue for eachportion of the image and for each portion of the image for each of aplurality of levels, wherein the characteristic data includes detectedvalues for a plurality of properties; c. determining a resultant codefor the characteristic data for each portion of the image and for eachportion of the image for each of a plurality of levels, wherein a set ofcodes is associated with each property, a certain code within the set isassociated with the detected value of the respective property, and theresultant code is calculated using a formula that considers eachdetected value and each property; d. assigning a color for each portionof the image, the color assignment based on a weighted formula thatconsiders the resultant code for each of the plurality of levels for therespective portion of the image, the weighted formula giving greaterconsideration to the resultant code for respective levels in closerproximity to the level in the image; and e. displaying the color foreach portion of the image, whereby differing colors displayed over theimage assist in determining the existence and location of tissueanomalies in three dimensions.
 51. A computer-readable medium thatconfigures a computer system to perform a method of displaying changesin tissue characteristics, over time, by color image, the methodcomprising the steps of: a. developing an image of tissue, the imagedivided into pre-determined portions and accompanied by data describingcoordinates of the tissue relative to a subject body for each portion ofthe image; b. receiving characteristic data of the tissue for eachportion of the image for separate instances in time, each portion of theimage having a first and a second coordinate relative to the image; c.determining a value of a difference in the characteristic data of thetissue for each portion of the image for the separate instances in time;d. associating a color to the value of the difference in thecharacteristic data for each portion of the image; and e. displaying thecolor for each portion of the image, whereby differing colors displayedover the image assist in determining the existence and location ofchanges in tissue characteristics over time for the subject body.
 52. Acomputer-readable medium that stores a program for imaging tissuecharacteristics, the program comprising: a. means for developing animage of tissue, the image divided into pre-determined portions andaccompanied by data describing a first and a second coordinate of thetissue relative to a subject body for each portion of the image; b.means for receiving characteristic data of the tissue for each portionof the image, each portion of the image having a first and a secondcoordinate relative to the image; c. means for associating a color tothe characteristic data for each portion of the image; and d. means fordisplaying the color for each portion of the image, whereby differingcolors displayed over the image assist in determining the existence oftissue anomalies in the subject body.
 53. A computer-readable mediumthat stores a program for imaging tissue characteristics, the programcomprising: a. means for developing an image of tissue, the imagedivided into pre-determined portions and accompanied by data describinga first and a second coordinate of the tissue relative to a subject bodyfor each portion of the image; b. means for receiving characteristicdata of the tissue for each portion of the image, each portion of theimage having a first and a second coordinate relative to the image; c.means for associating a code to the characteristic data for each portionof the image; d. means for associating a color to each code; and e.means for displaying the color for each portion of the image, wherebydiffering colors displayed over the image assist in determining theexistence of tissue anomalies.
 54. A computer-readable medium thatstores a program for creating color images of tissue density, theprogram comprising: a. means for developing an image of tissue, theimage divided into pre-determined portions and accompanied by datadescribing a first and a second coordinate of the tissue relative to asubject body for each portion of the image; b. means for receiving adensity value of the tissue for each portion of the image, each portionof the image having a first and a second coordinate relative to theimage; c. means for associating a color to the density value for eachportion of the image; and d. means for displaying the color for eachportion of the image, whereby different colors displayed over the imagerelate to different densities of tissue and thereby assist indetermining the existence of tissue anomalies.
 55. A computer-readablemedium that stores a program for creating three-dimensional color imagesof tissue density, the program comprising: a. means for developing animage of tissue, the image divided into pre-determined portions andaccompanied by data describing a first and a second coordinate of thetissue relative to a subject body for each portion of the image; b.means for receiving a density value of the tissue for each portion ofthe image, each portion of the image having a first and a secondcoordinate relative to the image; c. means for receiving a density valueof the tissue for each portion of the image for each of a plurality ofthird coordinate values and data describing the respective thirdcoordinate value of the tissue relative to the subject body for eachportion of the image; d. means for assigning a color for each portion ofthe image, the color assignment based on a formula that considers thedensity value of the tissue for each respective third coordinate value;and e. means for displaying the color for each portion of the image,whereby different colors displayed over the image relate to differentdensities of tissue in three-dimensions, thereby assisting indetermining the existence of tissue anomalies within the subject body.56. A computer-readable medium that stores a program for creating colorimages displaying tissue characteristics, the program comprising: a.means for developing an image of tissue, the image divided intopre-determined portions and accompanied by data describing a first and asecond coordinate of the tissue relative to a subject body for eachportion of the image; b. means for receiving characteristic data of thetissue for each portion of the image, wherein the characteristic dataincludes detected values for a plurality of properties; c. means fordetermining a resultant code for the characteristic data, wherein a setof codes is associated with each property, a certain code within the setis associated with the detected value of the respective property, andthe resultant code is calculated using a formula that considers eachdetected value and each property; d. means for associating a color toeach resultant code; and e. means for displaying the color for eachportion of the image, whereby differing colors displayed over the imageassist in determining the existence and location of tissue anomalies.57. A computer-readable medium that stores a program for creatingthree-dimensional color images displaying tissue characteristics, theprogram comprising: a. means for developing an image of tissue, theimage divided into pre-determined portions and accompanied by datadescribing a first and a second coordinate of the tissue relative to asubject body for each portion of the image; b. means for receivingcharacteristic data of the tissue for each portion of the image and foreach portion of the image for each of a plurality of levels, wherein thecharacteristic data includes detected values for a plurality ofproperties; c. means for determining a resultant code for thecharacteristic data for each portion of the image and for each portionof the image for each of a plurality of levels, wherein a set of codesis associated with each property, a certain code within the set isassociated with the detected value of the respective property, and theresultant code is calculated using a formula that considers eachdetected value and each property; d. means for assigning a color foreach portion of the image, the color assignment based on a weightedformula that considers the resultant code for each of the plurality oflevels for the respective portion of the image, the weighted formulagiving greater consideration to the resultant code for respective levelsin closer proximity to the level in the image; and e. means fordisplaying the color for each portion of the image, whereby differingcolors displayed over the image assist in determining the existence andlocation of tissue anomalies in three dimensions.
 58. Acomputer-readable medium that stores a program for displaying changes intissue characteristics, over time, by color image, the programcomprising: a. means for developing an image of tissue, the imagedivided into pre-determined portions and accompanied by data describingcoordinates of the tissue relative to a subject body for each portion ofthe image; b. means for receiving characteristic data of the tissue foreach portion of the image for separate instances in time, each portionof the image having a first and a second coordinate relative to theimage; c. means for determining a value of a difference in thecharacteristic data of the tissue for each portion of the image for theseparate instances in time; d. means for associating a color to thevalue of the difference in the characteristic data for each portion ofthe image; and e. means for displaying the color for each portion of theimage, whereby differing colors displayed over the image assist indetermining the existence and location of changes in tissuecharacteristics over time for the subject body.